PARK CITY — An estimated 100 million Americans will make online purchases Monday, capitalizing on Web deals offered by retailers on Cyber Monday — the Internet equivalent of Black Friday.

That's good news for Internet-based businesses such as Backcountry.com, an online retailer of high-end outdoor gear.

"It is definitely our kickoff to the shopping season," said Marit Fischer, brand marketing director for the Park City-headquartered company. "That's when people go online and want to find great deals for the holidays."

But Cyber Monday isn't Backcountry.com's biggest shopping day of the year, Fischer said. The busiest days, she said, are Dec. 13-15 — the last days people can shop online and receive their items in time for Christmas.

Backcounty.com's holiday shopping deals get under way Monday, with up to 50 percent off roughly 17,000 items, Fischer said. Those online deals will continue right up until Christmas.

Randall Sutherland of TopTenREVIEWS.com said the length of time online deals are offered is part of the reason Cyber Monday isn't the busiest Internet shopping day of the year.

"There will be a few (Cyber Monday bargains), but there will be more later," Sutherland told KSL's Bruce Lindsay on "Sunday Edition." "And as Christmas approaches, there may be even better deals. There isn't anything drop-dead about Monday."

Brianna Hermansen was at Target in Salt Lake City on Sunday afternoon, checking prices on items she may be interested in purchasing as Christmas gifts. Hermansen said she planned to compare those prices with online deals Monday.

"I've noticed there's a lot of free shipping (on Cyber Monday)," she said. "I plan on doing a lot of online shopping (Monday) … to get it all out of the way and take advantage of the free shipping."

Jude Newton, another Target shopper, said she actually made some online purchases on Black Friday. Newton said the Internet makes it easier to comparison shop.

"I didn't even know Cyber Monday existed," she said. "I tend to know what I want ahead of time.